1. Field of the Invention
The present invention concerns hydraulically operated actuators and, particularly, such actuators when used with diverters for directing the movement of tools used in conducting various operations on remotely located oil and/or gas wells, such as wells located subsea.
2. Description of the Prior Art
In performing completion and workover operations in subsea wells, tools are moved hydraulically into and out of well tubings through large radius flowline loops mounted on the submerged wells. In one type of subsea production system one pair of pump-down headers services several wells. Each well tubing is provided with wye-branched flow passageways to permit the conduct of operations either through a vertical conduit or through loops. Hydraulically operated tool diverters are required at each of the wells to enable the selective deflection of tools into the desired wells. A hydraulically operated TFL tool diverter designed to so direct passage of the TFL tools is shown and described in U.S. Pat. No. 3,881,516 entitled "Hydraulically Operated Diverter" by T. W. Childers et al. The hydraulically operated actuator of the present invention is an improvement in the actuator for such a diverter, particularly in the means for limiting the torsional force that can be generated on the paddle drive shaft of the diverter and in the means for effecting a static seal in the piston chamber.